Four Methods for Document Security
Document security is achieved through four layered techniques. For maximum security, all four techniques should be used simultaneously.
The first is related to the paper stock chosen for printing. Many special stocks are available that have security
features and restricted distribution. The second technique is to treat the paper with special inks, coatings, and/or chemicals to either overtly
dissuade someone from tampering, or covertly detect the result of tampering or counterfeiting. A third technique is to print a unique number, bar code, or
identifier on each document, so that no two are exactly the same. When used with a registration or tracking system, this technique is highly effective. These
three techniques share a common drawback: they add greatly to the manufacturing cost. Although the level of security possible from employing one or more physical
security methods is high, not all documents warrant the added cost.
The fourth technique is to use Amgrafs PixeLace to add security through complex and elaborate graphics. Graphical
effects can be used to add security to almost any document. Unlike most of the security features mentioned earlier, graphical effects in general
do not add to the overall production cost of a document. Of course, not every document needs expensive physical, chemical, or mechanical security
features to perform as intended, if the risk of fraud is minimal.
Rebate coupons and gift certificates are examples of documents that can be sufficiently protected by graphical techniques.
Given two documents that have the same value, a forger will most likely try to counterfeit the one with the least
number of security features. In many cases, just adding a few of the graphic effects listed below will protect a document:
- Subtle phantom images
- Prismatic colored backgrounds
- Lacey geometric patterns
- Void pantographs
- Fine-line relief of logos
- Layered borders
- Printed warning bands
- Moiré patterns
In North America, it is usually easy to verify a document via an on-line computer or telephone call.
This reduces, somewhat, the dependence on the printed document for absolute security. However, even in the U.S., there are many situations that are not
conducive for any verification other than a quick look at the document, such as tickets and passes. In many other parts of the world, communications
technology is not readily available, making the document itself a crucial element in a security effort. Documents that can not be easily verified need
to have the highest level of security.
The creator of a secure document should use as many graphical security features as possible to produce a verifiable
document that is difficult to forge, and resistant to photocopying. Complex graphics and colors, along with fine-line lacey borders and pantographs
are difficult to forge. The warning band also makes it clear to the forger that the producer of the document is committed to fighting fraud.
Some graphical features that are verifiable are micro-text and details, hidden images and messages, and subtle coloring.
Counterfeiting with Color Photocopiers
Simple counterfeiting has never been easier, because new color copier technology makes it easy to replicate any
document. However, color copiers do have limits in resolution and color gamut, and by understanding these limitations, documents can be
graphically protected. The most effective copy-resistant graphical techniques are fine-line reliefs, micro-text, and simulated watermarks
that can be seen only by holding the original document at an angle to the light.
Phantoms, void pantographs, and lacey borders and backgrounds are effective if used with other graphical
features because the copier can be adjusted to render fine detail with over-saturated bright colored areas, or adjusted to render the
saturated color with some loss of subtle areas. Always examine a customer's need for security in their printed forms, labels, tags, and
packages. By helping the customer to understand the risks, you will gain the trust and appreciation of your customer as well as his or her business.
Amgraf also offers LogoDot™, a patented method to embed a microscopic image of a corporate logo into a
halftone dot, to replace the conventional round dots typically used in traditional printing. When compared to conventional halftone dots,
LogoDots are much more difficult to faithfully reproduce with commercial photocopiers and scanners, resulting in easily detectable copies.
For more information, click to open
the white paper titled Creating Security Documents on the MECCA 2000 System.